Sign-tracking to non-drug reward is related to severity of alcohol-use problems in a sample of individuals seeking treatment

Background: A prominent neuroscientific theory of drug addiction is the incentive sensitization model. Individual differences in the tendency to ascribe motivational salience to cues that predict reward, and involuntary “sign-tracking” (orientation towards) such cues have been identified as potentially important in understanding vulnerability to addiction and relapse. However, to date this behaviour has not been assessed in a treatment-seeking clinical population, who typically represent those most susceptible to alcohol-related harms and episodes of relapse. This highlights a significant gap in the literature pertaining to incentive sensitization and drug dependence. 

Methods: Individuals accessing inpatient drug and alcohol services with alcohol as primary drug of concern were recruited to participate in a Cognitive Bias Modification (CBM) intervention. At the baseline assessment, participants completed various self-report measures (including the Alcohol Use Disorders Identification Test; AUDIT) in addition to a visual search task measuring sign-tracking to cues signalling monetary reward. At 3-month follow up, abstinence from alcohol was the primary outcome measure. All analyses and hypotheses were pre-registered. 

Results: At baseline (57 participants), AUDIT scores correlated with sign-tracking to signals of monetary reward. In a subsequent regression analysis sign-tracking, gender and self-reported alcohol craving predicted abstinence at 3-month follow up (41 participants). 

Conclusions: Our work demonstrates that involuntary sign-tracking to cues signalling non-drug reward is associated with problematic alcohol use and return to use at 3-month follow up, in a treatment-seeking sample. Whether this automatic prioritisation of cues signalling reward is a consequence or vulnerability for problematic alcohol use remains to be investigated.